Smart cities are vulnerable to cyber attacks aimed at weaknesses in their connected digital infrastructure, the UK's National Cyber Security Centre said.
Global metropolises use a range of connected devices and sensors that manage integrated systems, such as traffic light and CCTV networks.
Councils need to be better prepared to protect these systems from hackers who have the potential to disrupt critical networks, the NCSC said.
Such a scenario is reminiscent of a scene in the classic British film The Italian Job, said NCSC technical director Dr Ian Levy, and would be catastrophic for people who live and work in affected cities.
“One of the first Hollywood depictions of a cyber attack was against critical infrastructure,” he wrote in a blog.
"It was an attack against a city's centralised traffic management system in the 1969 film The Italian Job.
“As part of an elaborate heist, a dodgy computer professor [played by Benny Hill] switches magnetic storage tapes for the Turin traffic control to create a gridlock. Chaos ensues and the thieves escape with the gold.
"A similar 'gridlock' attack on a 21st-century city would have catastrophic impacts on the people who live and work there, and criminals wouldn't need physical access to the traffic control system to do it."
In response to the threat, the NCSC issued new guidance for councils and local authorities to help secure connected places and their underlying infrastructure.
The principles offer advice on designing and managing smart city networks to prevent mass data loss or rogue actors gaining access for spying or other purposes.
“Local authorities are using sensors and intelligent systems to improve our lives and make our cities more efficient and environmentally friendly,” Dr Levy said.
"These connected physical environments are just emerging in the UK, so now is the time to make sure we’re designing and building them properly."
